Robust and distributed neural representation of action values
Abstract
Studies in rats, monkeys, and humans have found action-value signals in multiple regions of the brain. These findings suggest that action-value signals encoded in these brain structures bias choices toward higher expected rewards. However, previous estimates of action-value signals might have been inflated by serial correlations in neural activity and also by activity related to other decision variables. Here, we applied several statistical tests based on permutation and surrogate data to analyze neural activity recorded from the striatum, frontal cortex, and hippocampus. The results show that previously identified action-value signals in these brain areas cannot be entirely accounted for by concurrent serial correlations in neural activity and action value. We also found that neural activity related to action value is intermixed with signals related to other decision variables. Our findings provide strong evidence for broadly distributed neural signals related to action value throughout the brain.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Raw data to reproduce this work is archived at Dryad https://doi.org/10.5061/dryad.gtht76hj0
Article and author information
Author details
Funding
Institute for Basic Science (IBS-R002-A1)
- Min Whan Jung
National Institute of Mental Health (DA 029330)
- Daeyeol Lee
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Timothy E Behrens, University of Oxford, United Kingdom
Version history
- Received: October 28, 2019
- Accepted: April 19, 2021
- Accepted Manuscript published: April 20, 2021 (version 1)
- Version of Record published: May 7, 2021 (version 2)
Copyright
© 2021, Shin et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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